diff options
| -rw-r--r-- | include/llvm/Support/type_traits.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/include/llvm/Support/type_traits.h b/include/llvm/Support/type_traits.h index 5000a8b859..32736b4141 100644 --- a/include/llvm/Support/type_traits.h +++ b/include/llvm/Support/type_traits.h @@ -49,6 +49,33 @@ struct is_class enum { value = sizeof(char) == sizeof(dont_use::is_class_helper<T>(0)) }; }; + +// enable_if_c - Enable/disable a template based on a metafunction +template<bool Cond, typename T = void> +struct enable_if_c { + typedef T type; +}; + +template<typename T> struct enable_if_c<false, T> { }; + +// enable_if - Enable/disable a template based on a metafunction +template<typename Cond, typename T = void> +struct enable_if : public enable_if_c<Cond::value, T> { }; + +namespace dont_use { + template<typename Base> char base_of_helper(const volatile Base*); + template<typename Base> double base_of_helper(...); +} + +/// is_base_of - Metafunction to determine whether one type is a base class of +/// (or identical to) another type. +template<typename Base, typename Derived> +struct is_base_of { + static const bool value + = is_class<Base>::value && is_class<Derived>::value && + sizeof(char) == sizeof(dont_use::base_of_helper<Base>((Derived*)0)); +}; + } #endif |